Screw lifting jack



June 2, 1925.

J. M. CANTWELL SCREW LIFTING JACK v Filed June 13,

Q NV YNTOR I BY I I v ATTOZie Patented June 2, 1925.

UNITED STATES JOHN M. CANTWELL, OF TAB-RYTOWN, NEW YORK.

SCREW LIFTING JACK.

Application filed June 13, 1924. Serial No. 719,714.

To all whom it may concern;

Be it known that I, JOHN M. CANTWELL, a citizen of the United States, residing at Tarrytown, in the county of 'VVestchester and State of New York, have invented certain new and useful Improvements in Screw Lifting Jacks, of which the following is a specification,

This, invention relates to screw lifting jacks, the object of the invention being to provide an improved screw lifting jack which may be easily extended, whereby both a. low and a very high lift may be obtained and which is particularly adapted for motor vehicles, is simple in construction and operation and strong, durable and powerful in use.

One of the objects of the invention is the provision of a combined lifting jack and rim tool in which the rim tool can not only be used for the application or removal of the shoes from the rims but to increase the height of the jack when desired.

A further object of this invention is the provision of an improved screw jack particularly adapted where a low lift is desired and which can however, be readily extended for a high lift or extra high lift as may be necessary.

In the drawings accompanying and forming a part of this specification, Fig. 1 is a vertical sectional view in partof this improved jack illustrating in dotted and full lines different positions of the tire tools; Fig. 2 is a detail part sectional View of the lifting screws in their raised position; Fig. 3 is a cross sectional view taken on line 33, Fig. 2; and Figs. 4 and 5 are detail views of the tire tools.

Similar characters of reference indicate corresponding parts in the several figures of the drawings.

Before explaining in detail the present improvement and mode of operation thereof, I desire to have it understood that the invention is not limited to the details of construction and arrangement of parts which are illustrated in the accompanying drawings, since the invention is capable of other embodiments, and that the phraseology which I employ is for the purpose of description and not of limitation.

This improved jack in its preferred form comprisesa suitable casing 2 having an oil chamber 4 provided with an oil inlet 5 and bolted to this casingis a base 3. Supported on the base by suitable ball bearings 6 is a bevel gear 7, pinned as at 8 to a rotatable tubular sleeve or shaft 9 extending into a recessed part 11 of the base and held in position against lengthwise movement by the projecting top portion 26 of the outer casing 2. Suitably supported by a wall of the oil chamber 4 is a mitre gear 10 in mesh with the bevel gear 7 this mitre gear being provided with a suitable spindle 9 by means of which and a suitable handle (not shown) the bevel gear 7 and the tubular sleeve or shaft 9 may be rotated. The base 3 is, as stated, recessed as at 11 for the reception of the lower end of the rotating sleeve or casing 9 and the reception of the two lifting screws hereinafter referred to,.hoth of which extend ,into the recessed part 11 of the base, thus permitting extra long screws to be used without increasing the height of the jack and so providing a very low lifting jack. Secured or pinned to ,the sleeve or shaft 9 at its upper end is a. threaded nut member 12, the threads of which engage a hollowlifting screw 13 and secured or pinned to this hollow lifting screw 13 is a companion threaded nut member 14, the'threads of which engage a second lifting screw 15, the'upper end of which is rotatabl provided with a supporting head or di 16.

- The periphery of this head .is provided with a pair of concave or arcuate recesses 17 for the reception of a pair of tire irons .18. These recesses are closed at the inner longitudinal side and at the outer longitudinal side are provided with openings of less diameter than the recess. The tire rim engaging irons 18 are shown provided with loop forming members or stirrups 19 and suitable extensions 20 for engaging the tire rims. These stirrups each have a transverse bar 21 formed so as to detachably fit into the recesses 17 of the head 16. Each pair 21 is flattened to a thickness corresponding substantially to the diameter of the opening in the recess 17, and has a width corresponding substantially to the larger diarm eter of the concave recess 17 so that when inserted, the bar will be entirely housed within the recess 17 and will rot-ate therein.

When the tire iron is swung to vertical position, the bar 21 may be shifted through the opening andout of the recess, but when 'swun "downwardly into operative position will locked within the recess.

In the position shown in dotted lines the tire irons can be used as extensions of the jack being suitabl held or clamped together by any suitable means as a strap 21'. The base 3 is provided with a suitable opening 22 for the third member 23 of the rim tool. The hollow lifting screw 13 is provided near its lower end with an annular groove 24 adapted to be engaged by an inwardly projecting tooth or key 25 located at the upper end of the casing 2 and shown formed on the inwardly turned portion 26 of that casing. This hollow screw 13 is also provided with a vertical slot or keyway 13' in which this tooth slides as the screw 13 is raised and lowered, and this tooth revents the rotation of the screw 13 until the groove 24 thereof comes into nosition to be engaged by the tooth. The inner lifting screw 15 is provided at its lower end with a stop pin 27 adapted to engage the nut member 14 and so limit the upward movement of this screw ,15 in the manner about to be described.

In operation on rotating the. mitre gear 10 the bevel gear 7 is rotated on its ball bearings and the sleeve 9 rotated. The rotation of this sleeve rotates the nut member 12, which is in engagement with the hollow screw 13, thereby forcing this screw upward to the desired height without the rotation thereof, since the sleeve and the nut member will rotate around the screw 13 and thus lift it. The rotation of the screw 13 being prevented at this time by the tooth or key 25 and side walls of the vertical slot or keyway 13, and as the nut member 14 is pinned 'to this hollow screw 13, the inner screw 15 lift the inner screw 15 the desired height,

and as both screws 13 and 15 are substantially the same length, it follows that double the lifting height 7 of the hollow screw is thus obtained so'that if the hollow screw is say eight inches high, practically a 16 inch lift is obtained by the two screws 13 and 15. The at the lower end of the screw 15 comingf into engagement with the-nut member Mfimits the upward movement of this screw. .Should it be desired to obtain a still further lift this is readily accomplished by positioning the tire irons 18 in the manner shown in dotted lines, thus providing an extraordinarily ,high lifting jack.

By reversing the bevel gear the jack screws are lowered.

From the foregoing it will be'seen that by the use of one screw alone, a very low lifting jack is obtained. By the use of two of practically equal length a double lift is obtained.

If desired, suitable openings may be made through the hollow tubular member 9 for oil to pass thereinto to lubricate the screws.

In spreading the rim it is merely necessary to use the upper tire irons 20 and not the lower one since the base of the jack can be used against the rim. In contracting the rim however, the lower tire iron 23 would be used in the usual manner.

It is to be understood that by describing in detail herein any particular form, structure or arrangement, it is not intended to limit the invention beyond the terms of the several claims or the requirements of the prior art.

Having thus explained the nature of my said invention and described a way of constructing and using the same, althou h without attempting to set forth allof t e forms in which it may be made, or all of the modes of its use, I claim:

1. In a screw lifting jack, the combinatioh of a supporting casing, a pair of telescopic lifting screws, means for lifting one of said screws without rotating it and for then rotating it to thereby lift the other screw, said means including a vertically extending rotatable tubular member entirely housed within said casing, and gear mechanism connected to the lower end thereof for rotating said member.

2. In a screw lifting jack, the combination of supporting means, a pair of telescopic lifting screws, means for lifting one of said screws without rotating it and for then rotating it to thereby lift the other screw said means including a rotatable vertically extending tubular member having substantially the same length as one of said screws and gear mechanism connected to said member adjacent to the lo'werpart ofthe supporting means for rotating said member.

3. In a lifting jack, the combination of a supporting casing, a pair of telescopic screws, a hollow vertical shaft housing said screws when collapsed, means for rotating said shaft, said shaft having interiorly thereof threaded means only at the upper end thereof cooperating with the outer screw, said outer screw .having interiorly thereof threaded means onl at the upper end thereof .cooperating with the inner screw, and also having a vertical keyway,

and a key carried by said casing above the w shaft and cooperatin with said keyway.

4. In a liftln ja'c the combination of three vertical te escopically mounted members adapted to rotate at predetermined times, the outer member having a threaded portion of less length than the length of such outer member 'located interiorly at the upper end thereof, the intermediate member having exterior threads cooperating with said threaded portion and also having a threaded portion of less length than the length of such intermediate member located interiorly at the upper end thereof, the inner member having exterior threads cooperating with said last threaded portion, and means for rotating the outer member.

5. In a lifting jack, the combination of a pair of telescopic outer and inner screws operatively connected together, a threaded sleeve embracing said outer screw for operating the same, a supporting casing housing said sleeve and having a projecting key located above the sleeve, and said outer screw having a vertical keywayfor receiv-' ing said key. i

6. In a lifting jack, the combination of a supporting casing, a pair of telescopic lifting screws, means for lifting one of said screws without rotating it and for then rotating it to lift the other screw,said means including a. verticall extending rotatable tubular member em racing one of said screws, and gear means located at the bottom of said casing and connectedto said tubular member for rotating the same.

7 The combination of a supporting base, a casing carried thereby, a vertically extending-tubular memberextending into said ca's ing, gear mechanism at the lower end of said caslng and connected to said member for rotating the same, a pair of telescopic lifting screws including an outer screw and an inner screw, means carried at the upper end of said tubular member and engaging said outer screw for lifting the same without rotating it, and means effective upon predetermined rotation thereof to lift the inner screw. v a

8. In a lifting jack, the combination of supporting means, a pair of telescopic screws, a l0ll0W vertical shaft housing substantially the major part of the length of said screws when collapsed, means for rotating said shaft, said shaft having interiorly and havin substantially the same length as one of sai screws, gear mechanism connected to the lower end of said member for rotating the same, means carried at the upper end of said member and engaging said outer screw for lifting the same without rotating it, means effective upon predeterminedlifting of said outer screw to permit the rotationthereof, and means at the upper end of said outer screw and engageable with the inner screw for lifting the latter upon rotation of the outer screw.

10. In a screw lifting jack, the combination of a base having a central recess, a pair of telescopic lifting screws normally extending into said recess, a rotary sleeve journaled in said recess, nieans for rotating said sleeve, means for connecting said sleeve with one of said screws for lifting the latter, means connecting said last screw with its companion screw for lifting it, and means for limiting the lifting movement of each of said screws, the limiting means ofone screw comprisinga stop and a cooperating annular groove.

11. In a screw lifting jack, the combination of a base having a recess,'a pair of telescopic lifting screws normally extending into said recess, a rotary sleeve journalled in said-recess, a nut member connecting said rotary sleeve with one of said screws for lifting it, a nut-member connecting said last screw withaits companion screw, and means including'a vertical slot and an annular groove carried by said first screw for permitting in sequence sliding and rotating movements of the screw.

12. In a screw lifting jack, the combination of a supporting base having a recess, a rotatable sleeve projecting into said recess, abevel gear'fixed'to said sleeve and mounted on said base, means for rotating said gear, a pair of telescopic lifting screws normally housed within said sleeve, means connecting the rotating sleeve with one of the screws, and means connecting said screw .housed within said casing, a gear secured to the lower end of said shaft, a nut secured interiorly at the upper end of said shaft, and a pair of interconnected telescopic screws housed within said shaft, one thereof cooperating with said nut and havingavertical keyway, and said casing having a key located above said-nut and extending into'said keyway.

14. The combination of a vertical non-rotatable casing, a rotatable sleeve housed therein, a pair of interconnected telescopic screws extending within said sleeve and one thereof operatively connected to the upper end of the sleeve, means for rotating the sleeve to lift said screws at predetermined times, said outer screw having a vertical keyway and said casing having a key lo-' cated above the upper end of said sleeve and adapted to project into said key way.

15. In a lifting jack, the combination of three vertical telescopic rotary members of substantially the same length adapted to be rotated one from the other at predetermined times, means adjacent to the bottom of the outer member for rotating the same thereby to simultaneously lift the intermediate and inner members without rotating them, and means at the top only of the interior memher for independently lifting without rotation the inner member during the rotation of the outer and intermediate members.

16. In a lifting jack, the combination of supporting means, a screw carried thereby, means for raising and lowering said screw, said screw adjacent to one end having a recess open at one side and closed at the opposite side, and a tire iron having a part in sertable thru the opening in the recess and adapted to be locked within the recess when the tire iron is in operative position.

mg and rotatable within the recess, said.

projecting portion having means housed within the recess for locking the tire iron when in operative position.

18. In a lifting jack, the combination of supporting means, a lifting screw. carried thereby, means for raising and lowering said screw, said screw at its outer end having ahead provided with a concave slot having an openingat one side of less diameter than the slot, and a tire iron comprising a shank terminating at one end in atire rim engaging portion and at the opposite end in a bar adapted to be entirely housed within said slot and rotatable therein, said bar having a width corresponding substantially to the diameter of said slot and a thickness corresponding substantially to the diameter of said opening.

Signed at Room 1822 Park Row Bldg, New York, N. Y., this 11th day of June, 1924.

JOHN M. OANTWELL 

